Control apparatus



H. H. JOHNSTON. CONTROL APPARATUS. APPLICATION FILED v4.29. 1911.

1,373,077. Patented Mar.29,1921.

a 5 I: a v 0 l /4 1% wnm l Z6, M 26-, 2/ ,2 24 WITNESSES: INVENTOR W Ha ward hfa/msfo/z BY W UNITED'STATES PATENT OFFICE.

HOWARD H. JOHNSTON, ornnenwoon PARK, PENNSYLVANIA, AssmNOR r0 WEST- INGHOUSE ELEOTRIOAND MANUFACTURING COMPANY, A CORPORATION OF PENN- SYLVANIA.

TocZZ whom it may concern: a 1

Be it known that I, HOWARD H. JOHNSTON, a citizen of the United States, anda resident of Edgewood Park, in the county of Allegheny and State of Pennsylvania, have invented a new and useful Improvement in Control Apparatus, of which the following is a specification. J y Y My invention relates to control apparatus and especially tothe automatic interlocking of control drums, or the like, under predetermined conditions.

The object of my invention is to provide a relatively simple, compact and durable structure of the above-indicated character which shall allow intermittent movement in one direction only, in accordance with the remote control of a governingelectrie circuit.

More specifically stated, it is the object of my invention to provide a control drum shaft having a a ratchet member provided with longitudinally-extending teeth and a cooperating normally disengaged rotatively stationary ratchet member for locking the drum shaft in certain positions, in accordance with current conditions in the mainmotor circuit, for example.

My invention may best be understood by referencev to the accompanying drawing,

wherein Figure l is'a view, in [front elevation, of a control apparatus constructed in accordance with my present inventlon; and

Fig. 2 is a diagrammatic view of a simplified control system utilizing the invention.

Referring to Fig. 1 ofthe drawing, the

structure shown comprises a control drum MC, of any familiar type, which is suitably mounted upona centrally located shaft 2 that extends through an appropriate bearlng member 3 andpreferably reststhereupon by 7 means of a collar or shoulder 4; a circular ratchet member 5 having a plurality ofteeth (5, the ratchet member being preferably de tachably secured to the drum shaft 2,-whereby ready replacements and. adjustments may be effected; anda cooperating stationary circular ratchet member 7 having a plurality of longitudinally-extending teeth 8 that are arranged to engage the teeth 6 of the movable ratchet member 5.

The control drum MC may be used for the well-known purpose ofgovernmg the auxiliary circuits for a railway-motor control Application filed January 29, 1317. Serial No..145,281.

ONTROL ArrAnArUs.

Specification of Letters Patent. Pate t d M 29 1921 which compressed air or other suitable operating medium may be admitted through a pipe or passage 12. Sincethe air-cylinder 11 and the cooperating piston that is secured to the rod or shaft 9 may be of any wellknown type, no further illustration or description thereof is deemed necessary, more specially since my invention is not restricted to the use of an electrically-controlled, fluidpressure actuated mechanism. The mechanical operation of the tructure just described, Without regard td he elec trical. connections associated therewith, may be set forth as follows: In the illustrated normal position of parts, the control drum MC, may be actuated in a forward or clockwise direction, when viewing the control drum from above, asindicated by the arrow, and such movement is unimpeded until fluid pressure is admitted into the operating cylinder 11 to raise the stationary ratchet member 7 into operative engagement with the rotatable ratchet member 5, whereuponthe teeth 8 and6 interlock to tem o- When fluid pressure is released from the cylinder 11, the control drum may be again actuated rarilyyprcvent further movement of t e i drum n the clockwise direction.

in .thedirection mentioned, until further interlocking engagement of the ratchet membersis effected. Backward movement of the control drum, that 1s to say, movement in a 'counter-cloclmdse direction, may be effected at any time during either the unlocked or locked position of the ,ratchet'members, by

reason of the relation of the teeth 6 and 8. Thus, the movement of the control drum in one direction may be intermittently arrested in accordance with predetermined conditions, whereas movement in the other direction is unrestricted at all times.

Reference may now be had to Fig. 2, wherein the system shown comprises an actuating coil 14 for governing the admission of fluid pressure to the operating cylinder 11, and a control circuit for that coil, including a source of energy, such as a battery cooperating contact members of the mastercontroller MC, and-cooperating contact members l5 of a limitswitch L of a familiar form.

The actuating coil 14 governs the position of a suitable needle-valve member for eiiecting communication 'between any suitable source of'fiuid pressure (not shown) and the operating cylinder ll, or for releasing fluid pressure from the cylinder to the at mo'sphere. Inasmuch as the construction just outlined is familiar to those skilled in they-tart, mmmorewer; is not specifically V essentialto my present invention, no fur- WayQVehicle motor or the like, to'raise the 1 deemed necessary ther illustration orfeiqjlanation thereof is The limit'switch is of a well-known type wherein the actuating coil 16 is connected in series relation with the windings of a rallmovable contact memberv 15 into its upper or operatlve position when the motor current atta ns a predetermined value and to allow the"movable contact memberto drop to its lower position to open an auxiliary circuit whengthe'motor current has again decreased below the predetermined value in question.

H The .operatl'onjof the control system may be briefly. described; as follows: Upon actuati'on ofthe-master controller from its oflt' switchL, when inits'upper or high-current "position, and conductor26 to the negative terminal of the battery B;

Upon the energization" of the actuating coill, thestationary ratchet member 7 is raised into engagement .with the movable "ratchet membert, which, as previously described, is secured to the shaft of the master controller drum, thereby preventing further movement of themaster, controller MC until the limit switch L; again drops'to its lower position. to open thefcircuit of the actuating coil 1st, whereupon" the stationary ratchet member7 recedes vto its normal position, and

further forward movement of the master controller is permltted.

.I do ,not wish to be restricted to the specific structural details or arrangement of circuits herein set forth, as various modifications thereofmay be efi'ected without departing from the spirit and scope of my invention. I desire, therefore, that only such limitations shall be imposed as are indicated in the appended claims.

I claim as my invention:

1. In control apparatus, the combination 1 with a rotatable ratchet member, of a complementary ratchet member normally disengaged therefrom, and power-actuated means responsive to predetermined electrical operating'conditions for automatically moving said complementary member into engagement with said rotatable member to arrest movement thereof.

2. In control apparatus, the combination with a control-drum shaft, of a member rotatablehvith said shaf, and having longi tudinally-extending teeth, a member having complementary teeth and normally disengaged from said rotatable member, and means responsive to predetermined electrical operating conditions for autmnatically eliecting operative engagement of the teeth of said members to arrest movement of said rotatable member.

3. In control apparatus, the combination with a control drum shaft, of a member rotatable with said shaft and having longi- V tudinally-extending teeth, a rotatively stationary member having coniplementary teeth and normally disengaged from said rotatable member, and remotely-controlled power-actuated yielding means responsive to predetermined electrical operating conditions for automatically efig'ecting operative engagement of the teeth of said members.

4. in control apparatus, the combination with a control drumshaft, of a member rotatable with said shaft and having longitudinally-extending teeth, a member having complementary teeth and normally disengaged from said rotatable member, and longitudinally-extending pneumatic means responsive to predetermined electrical operating conditions for automatically effecting operative engagement of said members to prevent movement of said drum shaft in the one direction.

5. In control apparatus, the combination with a rotatable ratchet member, of a complementary ratchet member normally disengaged therefrom, and means dependent upon predetermined electrical operating conditions for automatically effecting operative engagement of said ratchet members to prevent movement of the rotatable member inthe one direction.

In testimony whereof, I have hereunto subscribed my name this 20th day of J an.

HOWARD H. JOHNSTON. 

